1. Field of the Invention
The present invention relates to the field of display technology, and in particular to a color filter (CF) substrate and a display device.
2. The Related Arts
With the development of the display technology, flat panel display devices, such as liquid crystal displays (LCDs), due to a variety of advantages, such as high image quality, low power consumption, thin device body, and a wide range of applications, have been widely used in various consumer electronic products, such as mobile phones, televisions, personal digital assistants (PDAs), digital cameras, notebook computers, and desktop computers and are thus a main stream of display devices.
Most of the LCDs that are currently available in the market are backlighting LCDs, which comprise a liquid crystal display panel and a backlight module. The working principle of the liquid crystal display panel is that liquid crystal molecules are arranged between two parallel glass substrates and a plurality of vertical and horizontal tiny wires are arranged between the two glass substrates so that through application of electricity, the liquid crystal molecules are controlled to change direction in order to refract out light emitting from the backlight module to generate an image.
Generally, a liquid crystal display panel is composed of a color filter (CF) substrate, a thin-film transistor (TFT) substrate, liquid crystal (LC) interposed between the CF substrate and the TFT substrate, and sealant.
The color filter substrate, which is composed of color filters of three colors, including red (R), green (G), and blue (B), is an important part of a TFT LCD. As shown in FIG. 1, a conventional CF substrate is generally composed of a backing plate 100, a color filter 200 and a black matrix 300 arranged on the backing plate 100, and a plurality of spacers 400 arranged on the black matrix 300, wherein the color filter 200 comprises a plurality of red resist blocks 210, a plurality of green resist blocks 220, and a plurality of blue resist blocks 230 that are divided by the black matrix 300. The displaying characteristics of the TFT LCD require the color filter 200 to show properties and performances of high transmission rate and high color purity, large image, full color, high contrast, low reflection rate, high flatness, and good resistance.
Heretofore, methods that are adopted manufacture color resist blocks include pigment dispersion method, dying method, retro-printing method, thermal multilayer technology, and inkjet printing method. Due to various advantages in respect of color property, quality, and operability, the pigment dispersion method has been widely used and is the main stream manufacturing process. The operations of the pigment dispersion method are different for different mode of displaying.
However, in making color resist blocks using pigment dispersion, in addition to pigments that provide an effect of light filtration, additives, such as dispersion agents and rein must be added to the color resist material to facilitate impregnation and dispersion of the pigment. Due to the inclusion of the dispersion agent, the percentage of the pigment in the color resist material would be decreased, but the dispersion agent provide no contribution to light filtration so that the thickness of the color filter must be increased in order to obtain sufficiently high color purity. Increasing the color filter thickness, in addition to an increase of the cost, would also lower down light transmission rate of the entire display device, thereby leading to an increase of power consumption of the display panel and being adverse to environment protection.